UA 3591 then CA 3174 at O'Hare
Pittsburgh → Chicago → Guangzhou
Timetable, Chicago time
20:29UA 3591 from Pittsburgh at the gate
13:40CA 3174 to Guangzhou leaves the gate
17 h 11 apart on the timetable, overnight
CA 3174 leaves 17 h 11 after UA 3591 arrives on the timetable: more than half a day, so not a connection we count.